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421.
Jan Svoboda Klára Melánová Vítězslav Zima Ludvík Beneš Milan Pšenička Miroslav Pospíšil Petr Kovář 《Journal of molecular modeling》2016,22(6):143
Strontium phenylphosphonate intercalates with 1,2-diols (from 1,2-ethanediol to 1,2-hexanediol) were synthesized and characterized by X-ray diffraction, thermogravimetry, chemical analysis, and molecular simulation methods. Prepared samples exhibit a very good stability at ambient conditions. Structural arrangement calculated by simulation methods suggested formation of cavities surrounded by six benzene rings. Each cavity contained one molecule of diol and one molecule of water for the 1,2-ethanediol to 1,2-butanediol intercalates. In the case of 1,2-pentanediol two types of cavities alternated: one with diol molecules and another one with two water molecules. In the 1,2-hexanediol intercalate the benzene rings created two types of cavities containing one or two diol molecules, respectively, and this conformational variability led to a more disordered arrangement with respect to the models with shorter alkyl chains. Coordination of the oxygen atoms of the diols to the strontium atoms of the host follows the same pattern for all 1,2-diol intercalates except the 1,2-hexanediol intercalate, where these oxygen atoms can be mutually exchanged at their positions. The calculated basal spacings and structural models are in good agreement with experimental basal spacings obtained from X-ray powder diffraction and with other experimental results. 相似文献
422.
Qian?Liu Anping?Li Yijun?Tian Yu?Liu Tengfei?Li Cuntai?Zhang Jennifer?D.?Wu Xinwei?HanEmail author Kongming?WuEmail author 《Journal of hematology & oncology》2016,9(1):119
Background
The SIX family homeobox genes have been demonstrated to be involved in the tumor initiation and progression, but their clinicopathological features and prognostic values in non-small cell lung cancer (NSCLC) have not been well defined. We analyzed relevant datasets and performed a systemic review and a meta-analysis to assess the profile of SIX family members in NSCLC and evaluate their importance as biomarkers for diagnosis and prediction of NSCLC.Methods
This meta-analysis included 17 studies with 2358 patients. Hazard ratio (HR) and 95 % confidence interval (CI) were calculated to represent the prognosis of NSCLC with expression of the SIX family genes. Heterogeneity of the ORs and HRs was assessed and quantified using the Cochrane Q and I 2 test. Begg’s rank correlation method and Egger’s weighted regression method were used to screen for potential publication bias. Bar graphs of representative datasets were plotted to show the correlation between the SIX expression and clinicopathological features of NSCLC. Kaplan-Meier survival curves were used to validate our prognostic analysis by pooled HR.Results
The systematic meta-analysis unveiled that the higher expressions of SIX1-5 were associated with the greater possibility of the tumorigenesis. SIX4 and SIX6 were linked to the lymph node metastasis (LNM). SIX2, SIX3, and SIX4 were correlated with higher TNM stages. Furthermore, the elevated expressions of SIX2, SIX4, and SIX6 predicted poor overall survival (OS) in NSCLC (SIX2: HR?=?1.14, 95 % CI, 1.00–1.31; SIX4: HR?=?1.39, 95 % CI, 1.16–1.66; SIX6: HR?=?1.18, 95 % CI, 1.00–1.38) and poor relapse-free survival (RFS) in lung adenocarcinoma (ADC) (SIX2: HR?=?1.42, 95 % CI, 1.14–1.77; SIX4: HR?=?1.52, 95 % CI, 1.09–2.11; SIX6: HR?=?1.25, 95 % CI, 1.01–1.56).Conclusions
Our report demonstrated that the SIX family members play distinct roles in the tumorigenesis of NSCLC and can be potential biomarkers in predicting prognosis of NSCLC patients.423.
Innate immune surveillance in the blood is executed mostly by circulating monocytes, which recognise conserved bacterial molecules
such as peptidoglycan and lipopolysaccharide. Toll-like receptors (TLR) play a central role in microbe-associated molecular
pattern detection. Here, we compared the differences in TLR expression and cytokine production after stimulation of peripheral
blood cells with heat-killed Gram-negative and Gram-positive human pathogens Neisseria meningitidis, Escherichia coli, Staphylococcus aureus and Streptococcus pneumoniae. We found that TLR2 expression is up-regulated on monocytes after stimulation with S. aureus, S. pneumoniae, E. coli and N. meningitidis. Moreover, TLR2 up-regulation was positively associated with increasing concentrations of Gram-positive bacteria, whereas
higher concentrations of Gram-negative bacteria, especially E. coli, caused a milder TLR2 expression increase compared with low doses. Cytokines were produced in similar dose-dependent profiles
regardless of the stimulatory pathogen; however, Gram-negative pathogens induced higher cytokine levels than Gram-positive
ones at same concentrations. These results indicate that Gram-positive and Gram-negative bacteria differ in their dose-dependent
patterns of induction of TLR2 and TLR4, but not in cytokine expression. 相似文献
424.
In this study, porcine pancreatic lipase (EC 3.1.1.3) was immobilized on chitin and chitosan by adsorption and subsequent crosslinking with glutaraldehyde, which was added before (conjugation) or after (crosslinking) washing unbound proteins. Conjugation proved to be the better method for both supports. The properties of free and immobilized enzymes were also investigated and compared. The results showed that the pH optimum was shifted from 8.5 to 9.0 for both the immobilized enzymes. Also, the optimum temperature was shifted from 30 to 40 degrees C for chitin-enzyme and to 45 degrees C for chitosan-enzyme conjugates. The immobilization efficiency is low, but the immobilized enzymes have good reusability and stability (storage and operational). Besides these properties, the immobilized lipases were also suitable for catalyzing esterification reactions of fatty acids and fatty alcohols, both with a medium chain length. According to our results, esterification activities of immobilized lipases were two- and four-fold higher for chitosan- and chitin-enzyme, than for the free enzyme, respectively. The immobilization procedure shows a great potential for commercial applications of the immobilized lipase, a relatively low cost commercial enzyme. 相似文献
425.
Xianyong Wu Aaron Markir Yunkai Xu Edward C. Hu Kevin T. Dai Chong Zhang Woochul Shin Daniel P. Leonard Keun‐il Kim Xiulei Ji 《Liver Transplantation》2019,9(40)
Sulfur represents one of the most promising cathode materials for next‐generation batteries; however, the widely observed polysulfide dissolution/shuttling phenomenon in metal–sulfur redox chemistries has severely restricted their applications. Here it is demonstrated that when pairing the sulfur electrode with the iron metal anode, the inherent insolubility of iron sulfides renders the shuttling‐free nature of the Fe–S electrochemical reactions. Consequently, the sulfur electrode exhibits promising performance for Fe2+ storage, where a high capacity of ≈1050 mAh g?1, low polarization of ≈0.16 V as well as stable cycling of 150 cycles are realized. The Fe–S redox mechanism is further revealed as an intriguing stepwise conversion of S8 ? FeS2 ? Fe3S4 ? FeS, where a low volume expansion of ≈32.6% and all‐solid‐state phase transitions facilitate the reaction reversibility. This study suggests an alternative direction to exploit sulfur electrodes in rechargeable transition metal–sulfur batteries. 相似文献
426.
427.
Simcha?Lev-YadunEmail author Sarah?E.?Wyatt Moshe?A.?Flaishman 《Journal of Plant Growth Regulation》2004,23(4):301-306
Arabidopsis thaliana is gradually gaining significance as a model for wood and fiber formation.revolute/ifl1 is an important mutant in this respect. To better characterize the fiber system of therevolute/ifl1 mutant, we grew plants of two alleles (rev-9 in Israel andrev-1 in the USA) and examined the fiber system of the inflorescence stems using both brightfield and polarized light. Microscopic
examination of sections of plants belonging to the two different alleles clearly revealed that, contrary to previous views,
in 18 (13 in Israel and 5 in Ohio) out of 30 stems (20 in Israel and 10 in Ohio) the mutant produced the primary wavy fiber
system of the inflorescence stems. Our findings are further supported by the fact that fibers are seen in the figures published
in other studies of the mutant even when it was stated that there were no fibers. The impression of a total lack of the wavy
band of fibers is in many cases just a result of poorly lignified secondary walls. This specific gene that reduces lignification
in fibers is of great significance for biotechnological developments for the paper industry and thus for the global economy
and ecology. We propose thatrevoluta, the first name given to this mutant (Talbert and others 1995), is more appropriate thanifl1.
Online publication: 7 April 2005 相似文献
428.
429.
Summary Quantitative differentiation of microbial activity and saprophytic colonisation in wheat straw substrate during SSF is described. Wheat straw contains an active indigenous microbial flora. In both untreated and heat pretreated substrates a peak of microbial respiratory activities occurs generally after 24 h of fermentation; addition of actidione and streptomycin has no marked inhibitory effect. Quantitative differences between endogenous microbial respiration and respiration byPleurotus during the initial four days of SSF are least in the heat pretreated substrates and greater when microbiological pretreatment is used. In treatments subjected to 48 h anaerobic fermentation at 50°C, saprophytic colonization similar to that observed in sterile substrates is obtained. 相似文献
430.